Cell phones keep us socially connected, but new research suggests they actually reduce users’ social consciousness. In fact, the study showed that cell phone use was linked to more selfish behavior.

Researchers from the University of Maryland’s Robert H. Smith School of Business found that after a short period of cell phone use, people were less likely to partake in “prosocial” behavior — actions that are intended to help another person or society — compared with a control group. For example, after using a cell phone, study participants were more likely to turn down volunteer opportunities and were less persistent in completing word problems, even though they knew their answers would provide money for charity.

The same drop in prosocial tendencies occurred even when participants were simply asked draw a picture of their cell phones and think about using them.